xfs_bmbt_irec_t *map; /* buffer for user's data */
xfs_mount_t *mp; /* file system mount point */
int nex; /* # of user extents can do */
- int nexleft; /* # of user extents left */
int subnex; /* # of bmapi's can do */
int nmap; /* number of map entries */
struct getbmapx *out; /* output structure */
goto out_free_map;
}
- nexleft = nex;
-
do {
- nmap = (nexleft > subnex) ? subnex : nexleft;
+ nmap = (nex> subnex) ? subnex : nex;
error = xfs_bmapi_read(ip, XFS_BB_TO_FSBT(mp, bmv->bmv_offset),
XFS_BB_TO_FSB(mp, bmv->bmv_length),
map, &nmap, bmapi_flags);
goto out_free_map;
ASSERT(nmap <= subnex);
- for (i = 0; i < nmap && nexleft && bmv->bmv_length &&
- cur_ext < bmv->bmv_count; i++) {
+ for (i = 0; i < nmap && bmv->bmv_length &&
+ cur_ext < bmv->bmv_count - 1; i++) {
out[cur_ext].bmv_oflags = 0;
if (map[i].br_state == XFS_EXT_UNWRITTEN)
out[cur_ext].bmv_oflags |= BMV_OF_PREALLOC;
continue;
}
+ /*
+ * In order to report shared extents accurately,
+ * we report each distinct shared/unshared part
+ * of a single bmbt record using multiple bmap
+ * extents. To make that happen, we iterate the
+ * same map array item multiple times, each
+ * time trimming out the subextent that we just
+ * reported.
+ *
+ * Because of this, we must check the out array
+ * index (cur_ext) directly against bmv_count-1
+ * to avoid overflows.
+ */
if (inject_map.br_startblock != NULLFSBLOCK) {
map[i] = inject_map;
i--;
- } else
- nexleft--;
+ }
bmv->bmv_entries++;
cur_ext++;
}
- } while (nmap && nexleft && bmv->bmv_length &&
- cur_ext < bmv->bmv_count);
+ } while (nmap && bmv->bmv_length && cur_ext < bmv->bmv_count - 1);
out_free_map:
kmem_free(map);
*/
int
xfs_free_eofblocks(
- xfs_mount_t *mp,
- xfs_inode_t *ip,
- bool need_iolock)
+ struct xfs_inode *ip)
{
- xfs_trans_t *tp;
- int error;
- xfs_fileoff_t end_fsb;
- xfs_fileoff_t last_fsb;
- xfs_filblks_t map_len;
- int nimaps;
- xfs_bmbt_irec_t imap;
+ struct xfs_trans *tp;
+ int error;
+ xfs_fileoff_t end_fsb;
+ xfs_fileoff_t last_fsb;
+ xfs_filblks_t map_len;
+ int nimaps;
+ struct xfs_bmbt_irec imap;
+ struct xfs_mount *mp = ip->i_mount;
+
+ ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
/*
* Figure out if there are any blocks beyond the end
error = xfs_bmapi_read(ip, end_fsb, map_len, &imap, &nimaps, 0);
xfs_iunlock(ip, XFS_ILOCK_SHARED);
+ /*
+ * If there are blocks after the end of file, truncate the file to its
+ * current size to free them up.
+ */
if (!error && (nimaps != 0) &&
(imap.br_startblock != HOLESTARTBLOCK ||
ip->i_delayed_blks)) {
if (error)
return error;
- /*
- * There are blocks after the end of file.
- * Free them up now by truncating the file to
- * its current size.
- */
- if (need_iolock) {
- if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL))
- return -EAGAIN;
- }
+ /* wait on dio to ensure i_size has settled */
+ inode_dio_wait(VFS_I(ip));
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0,
&tp);
if (error) {
ASSERT(XFS_FORCED_SHUTDOWN(mp));
- if (need_iolock)
- xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return error;
}
}
xfs_iunlock(ip, XFS_ILOCK_EXCL);
- if (need_iolock)
- xfs_iunlock(ip, XFS_IOLOCK_EXCL);
}
return error;
}
/*
* Now that we've unmap all full blocks we'll have to zero out any
* partial block at the beginning and/or end. xfs_zero_range is
- * smart enough to skip any holes, including those we just created.
+ * smart enough to skip any holes, including those we just created,
+ * but we must take care not to zero beyond EOF and enlarge i_size.
*/
+
+ if (offset >= XFS_ISIZE(ip))
+ return 0;
+
+ if (offset + len > XFS_ISIZE(ip))
+ len = XFS_ISIZE(ip) - offset;
+
return xfs_zero_range(ip, offset, len, NULL);
}
xfs_fileoff_t stop_fsb;
xfs_fileoff_t next_fsb;
xfs_fileoff_t shift_fsb;
+ uint resblks;
ASSERT(direction == SHIFT_LEFT || direction == SHIFT_RIGHT);
if (direction == SHIFT_LEFT) {
+ /*
+ * Reserve blocks to cover potential extent merges after left
+ * shift operations.
+ */
+ resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
next_fsb = XFS_B_TO_FSB(mp, offset + len);
stop_fsb = XFS_B_TO_FSB(mp, VFS_I(ip)->i_size);
} else {
* If right shift, delegate the work of initialization of
* next_fsb to xfs_bmap_shift_extent as it has ilock held.
*/
+ resblks = 0;
next_fsb = NULLFSBLOCK;
stop_fsb = XFS_B_TO_FSB(mp, offset);
}
* into the accessible region of the file.
*/
if (xfs_can_free_eofblocks(ip, true)) {
- error = xfs_free_eofblocks(mp, ip, false);
+ error = xfs_free_eofblocks(ip);
if (error)
return error;
}
}
while (!error && !done) {
- /*
- * We would need to reserve permanent block for transaction.
- * This will come into picture when after shifting extent into
- * hole we found that adjacent extents can be merged which
- * may lead to freeing of a block during record update.
- */
- error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write,
- XFS_DIOSTRAT_SPACE_RES(mp, 0), 0, 0, &tp);
+ error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0,
+ &tp);
if (error)
break;
xfs_ilock(ip, XFS_ILOCK_EXCL);
error = xfs_trans_reserve_quota(tp, mp, ip->i_udquot,
- ip->i_gdquot, ip->i_pdquot,
- XFS_DIOSTRAT_SPACE_RES(mp, 0), 0,
+ ip->i_gdquot, ip->i_pdquot, resblks, 0,
XFS_QMOPT_RES_REGBLKS);
if (error)
goto out_trans_cancel;
projects / mirror_ubuntu-zesty-kernel.git / blobdiff